There could also be a new villain who is specifically after the Merlin's descendant. This villain would be a major character, constantly creating obstacles and threats for the protagonist. They might have their own motives related to power, revenge or some ancient prophecy.
One interesting plot could be the discovery of Merlin's descendant having unique magical abilities that are different from the normal wizarding world powers. For example, they might be able to communicate with ancient magical creatures in a way no one else can.
Yes, often there are. For example, the main character as a descendant of Merlin might have unique magical powers. They could be able to perform spells that are long forgotten or have an innate understanding of ancient magic. This can lead to all sorts of adventures, like exploring hidden chambers in Hogwarts that were sealed by Merlin himself and uncovering secrets that could change the wizarding world.
Often, there are other characters from the original Harry Potter series as well. For example, some fanfictions might include Hermione as a friend or mentor to the descendant. She can use her intelligence to help the main character understand their powers better. And of course, there could be some original characters created specifically for the fanfiction, like a mysterious wizard who also has a connection to Merlin's past.
Maybe he finds it in a hidden chamber at Hogwarts. There could be some ancient magic protecting it, but Harry, with his knack for getting into trouble and finding things, stumbles upon it.
Merlin's magic is very old and powerful. It could make Harry more attuned to the natural elements of magic. For example, he might be able to control the weather more easily during battles. His spell - casting could also become more instinctive and less reliant on wands as Merlin's magic was less wand - centric.
It could be a previously unknown student at Hogwarts. Maybe a shy Ravenclaw who has always been good at spells that require great intelligence and wisdom, which are traits often associated with Merlin.
The fanfic could start with the daughter of Merlin's staff being raised in a muggle family, unaware of her true identity. When she receives her Hogwarts letter, strange things start to happen. As she delves into the wizarding world, she begins to have visions related to Merlin's staff. She has to learn to control her powers, which are tied to the ancient magic of the staff. With the help of some wise professors and her newfound friends, she gradually uncovers the truth about her lineage and the great responsibility that comes with it.
His water - controlling ability as a son of Poseidon could be enhanced with Merlin - like magic. He might be able to turn water into different shapes or even solidify it in more complex ways, like creating ice sculptures with magical runes on them. Also, he could have a new form of precognition related to Merlin's seer abilities, seeing not just the immediate future related to water or battles, but a more far - reaching view of events.
Perhaps the fanfic's plot involves a character who is unknowingly Merlin's apprentice. They start having strange dreams about Merlin guiding them. As they explore these dreams, they learn skills like time - traveling magic which Merlin was known for. They then use this ability to go back in time and change certain events in the wizarding world's history for the better, all while trying to keep it a secret from the other Hogwarts students and faculty.